An electro-dynamic shaker is a type of linear motor used in vibration testing. Electro-dynamic shakers commonly require large currents to power the operation of the shakers. Linear amplifiers, including vacuum tubes or transistors, have been used to produce the large currents required. However, linear amplifiers can be expensive to purchase. Moreover, linear amplifiers can perform at a relatively low efficiency of approximately 30%, resulting in significant losses of power as heat during operation.